-transparent.png){kind=logo}
The effect of protein kinase A on the catalytic activity and phosphorylation of brain tryptophan hydroxylase was examined. Stimulation of endogenous protein kinase A by cyclic AMP or its analogues, dibutyryl-cyclic AMP and 8-thiomethyl-cyclic AMP, failed to activate tryptophan hydroxylase. The activation of tryptophan hydroxylase by calcium/calmodulin-phosphorylating conditions was not modified by cyclic AMP. Endogenous protein kinase A phosphorylated a large number of proteins and tryptophan hydroxylase could be identified as one substrate by sucrose gradient centrifugation, immunoprecipitation, and immunoblotting. These results indicate that tryptophan hydroxylase is phosphorylated by protein kinase A in brain and question whether this protein kinase exerts direct regulatory influence over tryptophan hydroxylase activity via phosphorylation.
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
May 1987,
The Journal of biological chemistry,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
January 1994,
Life sciences,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
July 1988,
Nucleic acids research,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
November 1994,
Biochimica et biophysica acta,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
November 1993,
Journal of neuroscience research,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
November 1996,
Neurochemistry international,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
July 1990,
FEBS letters,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
March 1993,
Biochemistry,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
June 2004,
Molecular and cellular biology,
P A Johansen, and
I Jennings, and
R G Cotton, and
D M Kuhn
July 1990,
Biochemical and biophysical research communications,
